Not so long ago, teenagers in trouble got grounded. They lost their evenings out, maybe the keys to the family car. But lately the art of family discipline has begun to reflect our digital age.

Not so long ago, teenagers in trouble got grounded. They lost their evenings out, maybe the keys to the family car. But lately the art of family discipline has begun to reflect our digital age.

Now parents seize cellphones, shut down Facebook, pull the plug on PlayStation.

That's how it went last year, when Iantha Carley's high-schooler got a midterm grade report that contained letters of the alphabet that were not A, B or C. Carley decreed there would be no more Facebook until he delivered a report card with better grades. The result: six weeks offline. "He lived," Carley reports, "with no lasting damage."

Her approach has become increasingly common as technology has changed so much about growing up, including what teenagers value most. For the digital generation, the priority isn't always going out with friends. It's being with them - in text, online.

As another school year begins, and parents hold their children accountable for what happens in and out of the classroom, the threat of losing digital privileges will be a recurring flashpoint.

"It's a modern version of grounding," says Richard Weissbourd, a Harvard psychologist. "It's like taking away a weekend or a couple of weekends. It's a deprivation of social connections in the same way."

Parents "know how important and vital it is to their teens' existence," says the report's co-author Amanda Lenhart. "They were getting them where it hurt."

In case of Cheryl Juneau's two sons, who get an hour of screen time a day, can't play with their iPods before beds are made and the playroom is clean. Never before has Juneau seen her sons approach these chores with such determination, she says.

The way Chelsea Welsh, 17, sees it, parents have not necessarily switched tactics for her generation, so much as expanded them. "We still get grounded," said Welsh, "but grounded now includes cellphones and Facebook being taken away.